How to Replace the Fuel Injection Plenum Gasket
If your car suddenly stalls, then the first culprit you could think of is the head gaskets. However, if the engine acts like it was seized, and would not turn over at all, then you're probably facing a problem with the intake manifold. You need to change the fuel injection plenum gasket and save the intake manifold. Below is a step-by-step guide to help you in replacing this component:
Difficulty level: Moderate
- Socket wrench
- Engine oil
- Torque wrench
Step 1: Unplug the negative battery cable from the terminal. Then, drain the engine coolant from the vehicle; it's commonly situated near the bottom of the radiator. You should then have access to the manifold by getting rid of a number of things that cover your way.
Step 2: Detach the engine cover by loosening the oil cap without completely pulling it off. Continue turning it counter clockwise and wait for it to stop completely. Once it does, pull the oil cap and oil cap tube out from the engine, proceeding to lifting the engine cover off the engine as well.
Step 3: Uninstall the air filter housing by removing the 2 Phillips screws on it, and then pulling off the throttle body hose end. Disengage the plug connected to the intake hose, and take out the whole assembly from the car.
Step 4: Mark each spark plug wires for reference. Then, pull the 3 plug wires before removing the serpentine belt. Remove the 3 alternator bolts and unplug the wiring from the back of the alternator. Take out the alternator and place it in a safe area.
Step 5: Take out the 6 electrical plugs of the fuel injector by squeezing on the metal locks and pulling them up. Remove the 3 electrical connectors leading to the MAP sensor as well. These connectors are usually on top of the intake manifold near the alternator.
Step 6: Detach all the vacuum lines that connect to the throttle body and intake manifold.
Step 7: Detach the fuel lines from the fuel rail. Look for the 2 plastic lines going to the fuel rail and are secured in place with small plastic clips. Simply squeeze the bottom of the clips, and pull them up on the fuel line.
Note: Some residual fuel may remain in one of the lines, so make sure you remove the lines slowly and cautiously.
Step 8: Remove the 10-mm nuts on the fuel rail with injectors to detach it from the lower intake manifold, and set the fuel rail aside. Then, find the bracket that connects the throttle body to the cylinder head. Using a 10-mm socket and extension, remove the bolt that secures the bracket in place. There's no need to remove the throttle cables from the throttle body. Simply fetch the assembly and set it aside.
Step 9: Take out all of the upper intake manifold bolts. Once unseated, remove the intake from the vehicle, and inspect if it's leaking internally. If the leaks have gone bad, you would most likely see a puddle of coolant inside the engine. Use old rags to clean up the leaked coolant, and make sure you clean the gasket mating surface of the lower intake manifold.
Step 10: Install the fuel injection plenum gasket into the new upper intake manifold. Next, return the upper intake in its place by aligning all the bolts and securing them properly.
Step 11: Reinstall the accessories, wirings, and fuel rail before refilling the coolant system. Then, start the vehicle and let it idle for a while. Check for leaks and overheating. Once you've confirmed that the fuel injection works fine, then you're ready for a test drive.